forked from rust-lang/rust
-
Notifications
You must be signed in to change notification settings - Fork 7
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Rollup merge of rust-lang#120460 - nnethercote:fix-120397, r=compiler-errors Be more careful about interpreting a label/lifetime as a mistyped char literal. Currently the parser interprets any label/lifetime in certain positions as a mistyped char literal, on the assumption that the trailing single quote was accidentally omitted. In such cases it gives an error with a suggestion to add the trailing single quote, and then puts the appropriate char literal into the AST. This behaviour was introduced in rust-lang#101293. This is reasonable for a case like this: ``` let c = 'a; ``` because `'a'` is a valid char literal. It's less reasonable for a case like this: ``` let c = 'abc; ``` because `'abc'` is not a valid char literal. Prior to rust-lang#120329 this could result in some sub-optimal suggestions in error messages, but nothing else. But rust-lang#120329 changed `LitKind::from_token_lit` to assume that the char/byte/string literals it receives are valid, and to assert if not. This is reasonable because the lexer does not produce invalid char/byte/string literals in general. But in this "interpret label/lifetime as unclosed char literal" case the parser can produce an invalid char literal with contents such as `abc`, which triggers an assertion failure. This PR changes the parser so it's more cautious about interpreting labels/lifetimes as unclosed char literals. Fixes rust-lang#120397. r? `@compiler-errors`
- Loading branch information
Showing
4 changed files
with
119 additions
and
30 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -1,16 +1,43 @@ | ||
// Note: it's ok to interpret 'a as 'a', but but not ok to interpret 'abc as | ||
// 'abc' because 'abc' is not a valid char literal. | ||
|
||
fn main() { | ||
let c = 'a; | ||
//~^ ERROR expected `while`, `for`, `loop` or `{` after a label | ||
//~| HELP add `'` to close the char literal | ||
match c { | ||
|
||
let c = 'abc; | ||
//~^ ERROR expected `while`, `for`, `loop` or `{` after a label | ||
//~| ERROR expected expression, found `;` | ||
} | ||
|
||
fn f() { | ||
match 'a' { | ||
'a'..='b => {} | ||
//~^ ERROR unexpected token: `'b` | ||
//~| HELP add `'` to close the char literal | ||
_ => {} | ||
'c'..='def => {} | ||
//~^ ERROR unexpected token: `'def` | ||
} | ||
let x = ['a, 'b]; | ||
//~^ ERROR expected `while`, `for`, `loop` or `{` after a label | ||
//~| ERROR expected `while`, `for`, `loop` or `{` after a label | ||
//~| HELP add `'` to close the char literal | ||
//~| HELP add `'` to close the char literal | ||
} | ||
|
||
fn g() { | ||
match 'g' { | ||
'g => {} | ||
//~^ ERROR expected pattern, found `=>` | ||
//~| HELP add `'` to close the char literal | ||
'hij => {} | ||
//~^ ERROR expected pattern, found `'hij` | ||
_ => {} | ||
} | ||
} | ||
|
||
fn h() { | ||
let x = ['a, 'b, 'cde]; | ||
//~^ ERROR expected `while`, `for`, `loop` or `{` after a label | ||
//~| HELP add `'` to close the char literal | ||
//~| ERROR expected `while`, `for`, `loop` or `{` after a label | ||
//~| HELP add `'` to close the char literal | ||
//~| ERROR expected `while`, `for`, `loop` or `{` after a label | ||
//~| ERROR expected expression, found `]` | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters